The desirability of combining physical activity and physical objects or counters as aids in teaching very young children to count have been well recognized for many years.
One approach, taught by U.S. Pat. No. 2,304,893 issued 1940 to Dickson provides a number peg board having successive adjacent regions marked, respectively, with ascending numbers in arabic and text and formed with corresponding numbers of sockets for receiving matching numbers of loose-piece, color-coded, pegs selected from a set and inserted therein by a child.
However, loose-piece pegs are easily lost and may be dislodged from the board, particularly with careless handling of the board, and can be swallowed by a child user or domestic pets. An increase in the size of the pegs to obviate swallowing by a child would result in a relative massive, heavy and cumbersome structure.
U.S. Pat. No. 3,714,721 issued 1971 to Tilley teaches a book comprising a board having a slideway removably receiving alternative work sheets marked with different math problems exposed to view through openings in the board. Seats are cut out adjacent the openings for receiving respective individual, correspondingly shaped, inserts marked on their fronts with solutions to the problems and color coded on rears viewable through the back of the board. A front cover is provided to ensure that the inserts remain in their seats during inspection of the back to check the color codes.
U.S. Pat. No. 3,715,816 issued 1973 to White shows a book with pictures of different animals on each leaf. Pieces simulating respective animals food can be releasably mounted on each leaf in a storage position or at a position adjacent the animal's mouth.
All the above proposals incur the disadvantages of a child handling small, loose-piece items with risk of loss or swallowing by the child or household pets.